About

Sameer Ankalgi — AI infrastructure and distributed systems. GPU inference, vLLM, Kubernetes. Microsoft, Zürich.

I build AI infrastructure and distributed systems — the layer that decides whether a model ships or stalls. I’m an engineer in GitHub AI Engineering at Microsoft in Zürich, working across GPU-based LLM inference and helping enterprise teams design, deploy, and scale AI workloads on Azure.

The work looks like this: profiling AlphaFold 2 on Azure H100 GPU HPC clusters until large-scale structure prediction was actually viable for a pharma customer. Serving DeepSeek across multi-GPU A100 clusters with vLLM and tensor parallelism, tuned for production throughput rather than benchmark throughput. The gap between those two numbers is most of my job.

I work out of Zürich — Microsoft’s office here and the lake within walking distance of it.

The path a token takes

Almost everything I care about lives somewhere on this diagram.

      request
         │
    ┌────▼─────┐   auth · quota · routing
    │ gateway  │
    └────┬─────┘
         │
    ┌────▼───────────┐   continuous batching
    │ vLLM scheduler │   paged attention
    └────┬───────────┘
         │
   ┌─────┴──────┬──────────┬──────────┐
   ▼            ▼          ▼          ▼
┌──────┐    ┌──────┐   ┌──────┐   ┌──────┐
│ TP 0 │    │ TP 1 │   │ TP 2 │   │ TP 3 │   tensor-parallel shards
└──┬───┘    └──┬───┘   └──┬───┘   └──┬───┘   H100 / A100 · NVLink
   └───────────┴────┬─────┴──────────┘
                    ▼
             ┌────────────┐
             │  KV cache  │   the thing that runs out first
             └────────────┘
Where the interesting failures happen: not in the model, in the plumbing around it.

A demo dies at the model. A production system dies at the scheduler, the cache, or the interconnect — and the person on the pager needs to know which.

How I got here

12+ years across the stack, and none of it started with GPUs:

The mix — knowing why a thing has to ship and being able to actually build it — is what I optimize for. Full detail on the CV.

What I think about

I published Reactive Programming Languages — A Survey, which is where the interest in runtime behaviour started.

Recent

Outside the laptop

Cycling around the Zürichsee in spring/summer, slow miles along the Limmat, occasional travel write-ups.

Find me

If you’re working on GPU inference, AI infrastructure, or the systems behind frontier models and want to compare notes, book a 30-minute chat.